Lenze VisiWinNet VisiWinNET Smart - Handbuch (Seite 205)

Project example
Configuring the alarm system
4
l
205 SHP−VWNS DE/EN 6.1
4.7 Configuring the alarm system
The purpose of an alarm system is to centrally detect and store error states or specific
alarms. The corresponding definitions of which variable triggers an alarm, how the alarm
is displayed and what additional information belongs to the alarm have to be specified in
the alarm editor. Notification regarding the variables that trigger the alarms is sent by
VisiWinNET
â
Smart to the variables core for monitoring. If a change in the value of a
variable occurs, the corresponding alarm is transferred to the application, where it is
displayed in special control elements.
VisiWinNET
â
Smart contains two control elements that allow the direct display of active
alarms:
AlarmList: All active alarms are displayed in the form of a list. The control element also
supports the acknowledgement of alarms.
AlarmLine:The space−saving variant that allows the user to see active alarms in the area at
the top or bottom of all forms.
In addition to the transfer of alarm data to the user interface, VisiWinNET
â
Smart allows
alarms to be stored in files. This makes it possible to review the production history of a
plant. The "HistoricalAlarmList" control component is used to display these recorded data
in the form of a list.
Alteration of a bit from the variables core is the means by which an alarm is controlled. It
is possible to choose whether the bit is set to "1" or "0" so that an alarm is triggered.
However, it is also possible to use an extension in order to check analogue variables to find
out whether they exceed certain limits. Alarms can be acknowledged by the user. An
acknowledgement feedback signal to the control system can also be implemented.
The appearance of alarms in the "AlarmLine" and "AlarmList" control elements is
parameterised by means of alarm classes. Alarm classes contain different parameters
(colours, status texts and symbols) that describe how an alarm is displayed. Each alarm
makes reference to an alarm class. The display parameters of an alarm class are thus
available to each alarm.
Alarm groups organise alarms into groups. In a way similar to language switching, it is
useful to group the individual functional elements of a plant. This promotes clarity and
endows the project with a modular structure. However, alarm groups also contain
additional parameters that permit group−wise deactivation or acknowledgement of
alarms.
The following example describes ...
ƒ how alarms that exist as bits in the variables core are generally configured, triggered
and displayed
ƒ the acknowledgement of alarms.
ƒ various display filters.
ƒ how analogue values are monitored.
First of all, the sources of the alarms have to be defined. Everything therefore begins during
process integration due to the fact that alarms are tied to specific variables. However,
because no real control data are available in the example, the triggering variables have to
be simulated by means of internal variables.